New camera on Palomar telescope will seek out supernovas, asteroids and more

A new eye on the variable sky just opened. The Zwicky Transient Facility, a robotic camera designed to rapidly scan the sky nightly for objects that move, flash or explode, took its first image on November 1.

The camera, mounted on a telescope at Caltech’s Palomar Observatory near San Diego, succeeds the Palomar Transient Factory. Between 2009 and 2017, the Palomar Transient Factory caught two separate supernovas hours after they exploded, one in 2011 (SN: 9/24/11, p. 5) and one earlier this year (SN: 2/13/17). It also found the longest-lasting supernova ever, from a star that seems to explode over and over (SN: 11/8/17).

The Zwicky survey will spot similar short-lived events and other cosmic blips, like stars being devoured by black holes (SN: 4/1/17, p. 5), as well as asteroids and comets. But Zwicky will work much faster than its predecessor: It will operate 10 times as fast, cover seven times as much of the sky in a single image and take 2.5 times as many exposures each night. Computers will search the images for any astronomical object that changes from one scan to the next.

The camera is named for Caltech astronomer Fritz Zwicky, who first used the term “supernova” in 1931 to describe the explosions that mark a star’s death (SN: 10/24/13).